Vehicle occupant detection system

ABSTRACT

Various implementations of an occupant detection system may be used in a vehicle to detect the presence of a living occupant (human or otherwise) and generate a warning. The warning may be communicated to another person(s) or to other vehicle systems to alert people in the vicinity of the vehicle. The system prevents injury and death to people and pets that may be accidentally within a parked car and unable to egress. The system may be integrated into a new vehicle or housed in a separate device that can be plugged into a power outlet within the vehicle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. patent application Ser. No.62/319,836, entitled “Vehicle Occupant Detection System,” filed Apr. 8,2016, the content of which is herein incorporated by reference in itsentirety.

BACKGROUND

Since 1998, 637 children have died as a result of heatstroke within aparked car. The annual average number of such deaths is 37. Thebreakdown of these incidents shows that 53% occur because the child isforgotten, and 29% occur because a child enters an unattended vehicleand can't get out.

Currently available occupant detection systems may include pressuresensors in seats or motion detection systems, but pressure sensor basedsystems may not be able to detect the presence of pets in the vehicle orchildren that may not be on the seat or of sufficient weight. The motiondetection systems may not be able to detect the presence of pets orchildren that are sleeping or not within the field of view of the motiondetection system.

Accordingly, systems and methods for detecting the presence of a vehicleoccupant within a vehicle are needed.

BRIEF SUMMARY

Various implementations of the invention may be used in a vehicle todetect the presence of a living occupant (human or otherwise) andgenerate a warning. The warning may be communicated to another person(s)or to other vehicle systems to alert people in the vicinity of thevehicle. The system prevents injury and death to people and pets thatmay be accidentally within a parked vehicle and unable to get out of thevehicle.

According to various implementations, an occupant detection systemwithin a vehicle includes an electrical signal sensor, an accelerometer,a carbon dioxide sensor, and a processor in communication with a memory.The processor executes computer-readable instructions stored on thememory, and the instructions cause the processor to receive a firstsignal from the electrical signal sensor indicating whether power to thevehicle is on or off, a second signal from the accelerometer indicatingwhether the vehicle is in motion, and a third signal from the carbondioxide sensor associated with a concentration of carbon dioxide in acabin of the vehicle. In response to the first signal indicating thatthe power is off and the second signal indicating that the vehicle isnot in motion, the instructions cause the processor to compare a rate ofchange of the data associated with the third signal with a thresholdlevel of an expected rate of change of carbon dioxide concentrationwithin the vehicle. And, in response to the rate of change of the dataassociated with the third signal exceeding the threshold level, theinstructions cause the processor to generate and communicate an alarmsignal.

In some implementations, the instructions cause the processor to storedata associated with the third signal in the memory at a first timeinterval periodically in response to the first signal indicating thatthe power is on or the second signal indicating that the vehicle is inmotion. The data associated with the third signal corresponds to acarbon dioxide concentration within the vehicle. In response to thefirst signal indicating that the power is off and the second signalindicating that the vehicle is not in motion, the instructions cause theprocessor to store the data associated with the third signal in thememory at a second time interval periodically. The second time intervalis more frequent than the first time interval.

The instructions may also cause the processor to compare the dataassociated with the third signal with a threshold level of carbondioxide concentration within the vehicle, and in response to the dataassociated with the third signal exceeding the threshold level of carbondioxide concentration, generate and communicate the alarm signal.

The occupant detection system may also include a temperature sensor fordetecting a temperature in the vehicle, according to someimplementations. The instructions further cause the processor to receivea fourth signal from the temperature sensor. The fourth signal isassociated with the temperature in the vehicle. The threshold level ofan expected rate of change of the carbon dioxide concentrations includesa first threshold level in response to the fourth signal indicating thatthe temperature in the vehicle is within a first temperature range and asecond threshold level in response to the fourth signal indicating thatthe temperature in the vehicle is within a second temperature range. Forexample, the first threshold level may be lower than the secondthreshold level and the first temperature range is higher than thesecond temperature range. In addition, the second time interval maydecrease in response to the fourth signal indicating that thetemperature in the vehicle exceeds a pre-defined temperature threshold.

In some implementations, the electrical signal sensor, theaccelerometer, the carbon dioxide sensor, and the processor are disposedin a housing. The housing may include a plug for engaging a plugreceptacle within a cabin of the vehicle, according to oneimplementation.

In some implementations, the processor is in electrical communicationwith an on-board diagnostic computing system in the vehicle.

In some implementations, the system further includes a cellular modem,and the alarm signal may be communicated to a cellular device, such as acellular phone or tablet, via the cellular modem.

In some implementations, the occupant detection system further includesa local area network communication device, and the alarm signal may becommunicated to a computing device disposed outside of the vehicle viathe local area network communication device.

In some implementations, the instructions further cause the processor tocommunicate with a communication bus of the vehicle, and the alarmsignal includes an instruction to open at least one door and/or windowof the vehicle, turn on an air conditioning system of the vehicle, turnon the vehicle, communicate with an on-board communication system, sounda horn of the vehicle, and/or flash headlights of the vehicle.

According to other various implementations, an occupant detection systemwithin a vehicle includes an electrical signal sensor, an accelerometer,a carbon dioxide sensor, and a processor in communication with a memory.The processor executes computer-readable instructions stored on thememory, and the instructions cause the processor to: (1) receive a firstsignal from the electrical signal sensor indicating whether power to thevehicle is on or off, a second signal from the accelerometer indicatingwhether the vehicle is in motion, and a third signal from the carbondioxide sensor indicating a concentration of carbon dioxide in a cabinof the vehicle, (2) in response to the first signal indicating that thepower is off and the second signal indicating that the vehicle is not inmotion, compare the data associated with the third signal with athreshold level of expected carbon dioxide concentration within thevehicle, and (3) in response to the data associated with the thirdsignal exceeding the threshold level, generate and communicate an alarmsignal.

In some implementations, the instructions may cause the processor tostore data associated with the third signal in the memory at a firsttime interval periodically in response to the first signal indicatingthat the power is on or the second signal indicating that the vehicle isin motion. The data associated with the third signal corresponds to acarbon dioxide concentration. In addition, the instructions may causethe processor to store the data associated with the third signal in thememory at a second time interval periodically in response to the firstsignal indicating that the power is off and the second signal indicatingthat the vehicle is not in motion. The second time interval may be morefrequent than the first time interval.

In some implementations, the data associated with the third signalincludes an absolute value of the data. The instructions may furthercause the processor to compare a rate of change of the data associatedwith the third signal with a threshold level of an expected rate ofchange of carbon dioxide concentration within the vehicle, and inresponse to the rate of change data associated with the third signalexceeding the threshold level of expected rate of change of carbondioxide concentration, generate and communicate the alarm signal.

BRIEF DESCRIPTION OF THE DRAWINGS

The components in the drawings are not necessarily to scale relative toeach other. Like reference numerals designate corresponding partsthroughout the several views.

FIG. 1 illustrates a block diagram of the occupant detection systemaccording to one implementation.

FIG. 2 illustrates a schematic of a housing that includes components ofthe occupant detection system, according to one implementation.

FIG. 3 illustrates a schematic of a housing and power outlet plug havinga power cable extending between them, according to one implementation.

DETAILED DESCRIPTION

Various implementations of an occupant detection system may be used in avehicle to detect the presence of a living occupant (human or otherwise)and generate a warning. The warning may be communicated to anotherperson(s) or to other vehicle systems to alert people in the vicinity ofthe vehicle. The system prevents injury and death to people and petsthat may be accidentally within a parked car and unable to get out ofthe vehicle. The system may be integrated into a newly designed vehicleor housed in a separate device that can be plugged into a power outletwithin a cabin of the vehicle.

The system is based on the detection of carbon dioxide, which naturallyoccurs as living creatures exhale. In a confined space with poor orwithout ventilation, carbon dioxide levels rise when a living creatureis present within the space. Previous research has shown a linearincrease in carbon dioxide concentration in an unventilated vehicle atrest. With ventilation and when moving, the carbon dioxide level has anexponential increase and reaches a steady-state value. The timederivative of the carbon dioxide levels increases are dependent onnumber of passengers, breathing rate, carbon dioxide concentration inthe expiration, and the volume of the cabin. By combining data thatdetermines whether the vehicle is parked with data regarding temperatureand carbon dioxide level rates of change, a determination about thepresence of an occupant in a parked vehicle may be made.

An exemplary block diagram of the system is provided in FIG. 1. As shownin FIG. 1, the system 10 includes a microprocessor 12 that is inelectrical communication (e.g., digital communication) with atemperature sensor 14, a carbon dioxide sensor 16, an accelerometer 18,and one or more communication devices. The communication devices mayinclude a cellular modem 20 and/or a local area network device 22, suchas a Bluetooth™ device. In addition, the system 10 may also detectwhether the vehicle power is on or off using an electrical signal sensor13. For example, if the vehicle is on, then the system 10 receives 12Vfrom the vehicle. And, if the vehicle is switched off, the 12V is notpresent. The temperature sensor 14 detects a temperature within thecabin of the vehicle, the carbon dioxide sensor 16 detects carbondioxide levels within the cabin of the vehicle, and the accelerometer 18detects whether the vehicle is in motion.

Signals from the sensors 14, 16, and 18 are received by themicroprocessor 12, and the microprocessor 12 communicates with thesensors 14, 16, 18 regarding the frequency for signal collection, thetime period for storing the received signals, and/or operation modesrelated to the received signals. In the implementation of FIG. 1,microprocessor 12 is in electrical communication with a voltageregulator 24, which is in electrical communication with a power supply26. And, the microprocessor 12 is in direct electrical communicationwith the power supply 26 via a digital bit 28.

In some implementations, such as the implementation shown in FIGS. 2 and3, the components of the system shown in FIG. 1 are disposed within ahousing 100. The housing 100 shown in FIG. 2 is physically andelectrically coupled with a power outlet plug 150 for plugging into anelectrical outlet or receptacle within the cabin of the vehicle. Thehousing 100 shown in FIG. 3 is electrically coupled to a power outletplug 150 via power cable 152, but it is not physically coupled to theplug 150. These implementations allow the system to be used in anyvehicle.

In other implementations, one or more of the components shown in FIG. 1are integrated into the vehicle during the design phase. For example, insome implementations, the accelerometer, electrical signal sensor,carbon dioxide sensor, and/or temperature sensor are installed in thevehicle, and the microprocessor receives signals from these sensors viathe vehicle communication bus. For example, in certain implementations,the microprocessor is part of or configured for communicating with an onboard diagnostics system (OBDII) of the vehicle, which receives signalsfrom these sensors. Alternatively or additionally, the system isconfigured for receiving a signal from the OBDII that the vehicle isparked. The microprocessor determines whether the vehicle is parked andoff, monitors carbon dioxide and/or temperature rise levels according tothe modes described above, and communicates messages to other vehiclesystems or an external computing device in response to the systemdetecting carbon dioxide and/or temperature rise levels exceeding thepreset thresholds.

In general, the microprocessor 12 receives signals from the sensors 14,16, and 18 and identifies an operation mode for the system. According tocertain implementations, the operation modes include: a transport mode,a monitor mode, and an alarm mode. The system operates in transport modein response to detecting that power is being supplied to the vehicleand/or the vehicle is in motion. In the transport mode, the carbondioxide sensor 16 and the temperature sensor 14 sample carbon dioxidelevels and temperature, respectfully, within the cabin of the vehicle ata first frequency, such as, for example, every minute. In someimplementations, this information is stored on a first in, first outbasis for a certain time period, such as, for example, five minutes. Inother implementations, the first frequency and/or time for storage maybe decreased or increased. In some implementations, an absolute value ofthe data is stored.

The system enters the monitor mode in response to detecting that thevehicle power is off and the vehicle is not in motion, such as when thevehicle is parked. Having the system detect both markers allows thesystem to remain in transport mode when the vehicle has power but ismotionless or when the system is not receiving an electrical signal fromthe vehicle but the vehicle is moving. The latter situation occurs, forexample, when components of the system are disposed within a housing,such as housing 100 shown in FIGS. 2 and 3, and the power outlet plug isunplugged from the plug receptacle within the cabin of the vehicle. Inmonitor mode, the system samples carbon dioxide levels and temperatureat a second frequency that is higher than the first frequency. Forexample, the second frequency may be about every 30 seconds. In someimplementations, this information is stored for an unlimited time periodor for another discrete time period, which can be the same or differentfrom the time period of storage in the transport mode.

The system enters the alarm mode in response to detecting that a rate ofincrease in the carbon dioxide levels exceeds a first predeterminedcarbon dioxide threshold. The system also enters the alarm mode if therate of increase in carbon dioxide levels exceeds a second predeterminedcarbon dioxide threshold, which is lower than the first predeterminedcarbon dioxide threshold, and the temperature (or rate of temperaturerise) exceeds a predetermined temperature threshold according to someimplementations. In alternative implementations, the absolute values,rather than rate of change, of carbon dioxide concentration andtemperature, are used to determine when to enter the alarm mode. When inalarm mode, the system generates an alarm signal to alert another personor people within the vicinity of the vehicle that there is an occupantwithin the vehicle. For example, the alarm signal causes a vehicle alarmto sound, or the alarm signal causes a visual, audible, and/orvibro-tactile message to be communicated to a user of a mobilecommunication device of a designated person(s). Alternatively or inaddition to the above, the alarm signal may cause a message to becommunicated to emergency personnel or emergency vehicle serviceprovider. Alternatively or in addition to the above, the alarm signalmay cause a response from one or more other vehicle systems, such aslowering one or more windows, opening or unlocking one or more doors,turning on the power, the air conditioning system, communication with anon-board communication system, sounding the horn, and/or flashingheadlights.

Signals communicated from the system via the local area network device22 and cellular modem 20 include, for example, warning messages orinformation about the carbon dioxide and/or temperature levels withinthe vehicle, according to some implementations. For example, the alarmsignal may cause the portable computing device or cellular device togenerate an audible, visual, and/or vibro-tactile warning message to theuser.

Furthermore, in some implementations, the system includes hardware orsoftware installed on a vehicle operator's portable computing device orcomputing device for communicating with the vehicle-side communicationdevice(s), such as device 22 or modem 20, of the system. The hardware orsoftware can be configured for receiving a telephone call, a textmessage, and/or another alarm feedback response, such as audible,visual, and/or vibro-tactile feedback. In addition, the hardware orsoftware on the portable computing device or computing device may beused by an operator to select feedback preferences and/or input phonenumbers to call and/or text in response to the system entering the alarmmode.

The devices recited in the appended claims are not limited in scope bythe specific devices and methods of using the same described herein,which are intended as illustrations of a few aspects of the claims. Anydevices or methods that are functionally equivalent are intended to fallwithin the scope of the claims.

Various modifications of the devices and methods in addition to thoseshown and described herein are intended to fall within the scope of theappended claims. Further, while only certain representative devices andmethod steps disclosed herein are specifically described, othercombinations of the devices and method steps are intended to fall withinthe scope of the appended claims, even if not specifically recited.Thus, a combination of steps, elements, components, or constituents maybe explicitly mentioned herein; however, other combinations of steps,elements, components, and constituents are included, even though notexplicitly stated. The term “comprising” and variations thereof as usedherein is used synonymously with the term “including” and variationsthereof and are open, non-limiting terms. Those skilled in the art whoreview this disclosure will readily appreciate that many modificationsare possible (e.g., variations in sizes, dimensions, structures, shapesand proportions of the various elements, values of parameters, mountingor layering arrangements, use of materials, colors, orientations, etc.)without materially departing from the novel teachings and advantages ofthe subject matter described herein. For example, elements shown asintegrally formed may be constructed of multiple parts or elements, theposition of elements may be reversed or otherwise varied, and the natureor number of discrete elements or positions may be altered or varied.Other substitutions, modifications, changes and omissions may also bemade in the design, operating conditions and arrangement of the variousexemplary embodiments without departing from the scope of the presentembodiments.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims.

The invention claimed is:
 1. An occupant detection system within avehicle comprising: an electrical signal sensor; an accelerometer; acarbon dioxide sensor; and a processor in communication with a memory,wherein the processor executes computer-readable instructions stored onthe memory, said instructions cause the processor to: receive a firstsignal from the electrical signal sensor indicating whether power to thevehicle is on or off, receive a second signal from the accelerometerindicating whether the vehicle is in motion, and receive a third signalfrom the carbon dioxide sensor associated with a concentration of carbondioxide in a cabin of the vehicle, in response to the first signalindicating that the power is on or the second signal indicating that thevehicle is in motion, store data associated with the third signal in thememory at a first time interval periodically, in response to the firstsignal indicating that the power is off and the second signal indicatingthat the vehicle is not in motion, compare a rate of change of the dataassociated with the third signal with a threshold level of an expectedrate of change of carbon dioxide concentration within the cabin of thevehicle and store the data associated with the third signal in thememory at a second time interval periodically, wherein the second timeinterval is more frequent than the first time interval, and in responseto the rate of change of the data associated with the third signalexceeding the threshold level, generate and communicate an alarm signal.2. The occupant detection system of claim 1, wherein the instructionsfurther cause the processor to compare the data associated with thethird signal with a threshold level of carbon dioxide concentrationwithin the vehicle, and in response to the data associated with thethird signal exceeding the threshold level of carbon dioxideconcentration, generate and communicate the alarm signal.
 3. An occupantdetection system within a vehicle comprising: an electrical signalsensor; an accelerometer; a temperature sensor for detecting atemperature in the vehicle; a carbon dioxide sensor; and a processor incommunication with a memory, wherein the processor executescomputer-readable instructions stored on the memory, said instructionscause the processor to: receive a first signal from the electricalsignal sensor indicating whether power to the vehicle is on or off,receive a second signal from the accelerometer indicating whether thevehicle is in motion, receive a third signal from the carbon dioxidesensor associated with a concentration of carbon dioxide in a cabin ofthe vehicle, and receive a fourth signal from the temperature sensor,the fourth signal being associated with the temperature in the vehicle,in response to the first signal indicating that the power is off and thesecond signal indicating that the vehicle is not in motion, compare arate of change of the data associated with the third signal with a firstthreshold level of an expected rate of change of the carbon dioxideconcentrations within the cabin of the vehicle in response to the fourthsignal indicating that the temperature in the vehicle is within a firsttemperature range and compare the rate of change of the data associatedwith the third signal with a second threshold level of the expected rateof change of carbon dioxide concentration within the cabin of thevehicle in response to the fourth signal indicating that the temperaturein the vehicle is within a second temperature range, and in response tothe rate of change of the data associated with the third signalexceeding the first threshold level or the second threshold level,generate and communicate an alarm signal.
 4. The occupant detectionsystem of claim 3, wherein the first threshold level is lower than thesecond threshold level and the first temperature range is higher thanthe second temperature range.
 5. The occupant detection system of claim4, wherein the second time interval decreases in response to the fourthsignal indicating that the temperature in the vehicle exceeds apre-defined temperature threshold.
 6. The occupant detection system ofclaim 1, wherein the electrical signal sensor, the accelerometer, thecarbon dioxide sensor, and the processor are disposed in a housing, thehousing comprising a plug for engaging a plug receptacle within a cabinof the vehicle.
 7. The occupant detection system of claim 1, wherein theprocessor is in electrical communication with an on-board diagnosticcomputing system in the vehicle.
 8. The occupant detection system ofclaim 1, further comprising a cellular modem, and wherein the cellularmodem is for communicating the alarm signal to a cellular device over awireless communication network.
 9. The occupant detection system ofclaim 1, further comprising a local area network communication device,and wherein the local area network communication device is forcommunicating the alarm signal to a computing device disposed outside ofthe vehicle over a wireless communication network.
 10. The occupantdetection system of claim 1, wherein the instructions further cause theprocessor to communicate with a communication bus of the vehicle, andthe alarm signal comprises an instruction to open at least one door ofthe vehicle.
 11. The occupant detection system of claim 1, wherein theinstructions further cause the processor to communicate with acommunication bus of the vehicle, and the alarm signal comprises aninstruction to open at least one window of the vehicle.
 12. The occupantdetection system of claim 1, wherein the instructions further cause theprocessor to communicate with a communication bus of the vehicle, andthe alarm signal comprises an instruction to turn on an air conditioningsystem of the vehicle.
 13. The occupant detection system of claim 1,wherein the instructions further cause the processor to communicate witha communication bus of the vehicle, and the alarm signal comprises aninstruction to turn on the vehicle.
 14. The occupant detection system ofclaim 1, wherein the instructions further cause the processor tocommunicate with a communication bus of the vehicle, and the alarmsignal comprises an instruction to communicate with an on-boardcommunication system.
 15. The occupant detection system of claim 1,wherein the instructions further cause the processor to communicate witha communication bus of the vehicle, and the alarm signal comprises aninstruction to sound a horn of the vehicle.
 16. The occupant detectionsystem of claim 1, wherein the instructions further cause the processorto communicate with a communication bus of the vehicle, and the alarmsignal comprises an instruction to flash headlights of the vehicle. 17.An occupant detection system within a vehicle comprising: an electricalsignal sensor; an accelerometer; a carbon dioxide sensor; and aprocessor in communication with a memory, wherein the processor executescomputer-readable instructions stored on the memory, said instructionscause the processor to: receive a first signal from the electricalsignal sensor indicating whether power to the vehicle is on or off,receive a second signal from the accelerometer indicating whether thevehicle is in motion, and receive a third signal from the carbon dioxidesensor associated with a concentration of carbon dioxide in a cabin ofthe vehicle, in response to the first signal indicating that the poweris on or the second signal indicating that the vehicle is in motion,store data associated with the third signal in the memory at a firsttime interval periodically, in response to the first signal indicatingthat the power is off and the second signal indicating that the vehicleis not in motion, compare the data associated with the third signal witha threshold level of expected carbon dioxide concentration within acabin of the vehicle and store the data associated with the third signalin the memory at a second time interval periodically, wherein the secondtime interval is more frequent than the first time interval, and inresponse to the data associated with the third signal exceeding thethreshold level, generate and communicate an alarm signal.
 18. Theoccupant detection system of claim 17, wherein the data associated withthe third signal comprises an absolute value of the data.
 19. Theoccupant detection system of claim 17, wherein the data associated withthe third signal comprises a rate of change of the data associated withthe third signal, and the threshold level of expected carbon dioxideconcentration comprises an expected rate of change of carbon dioxideconcentration within the cabin of the vehicle.